JPH0463809A - Ethylene terpolymer and its manufacturing method - Google Patents

Abstract

PURPOSE:To improve the balance among cuttability, tear resistance, etc., without degrading the resistance to environmental stress crack, impact strength, etc., by specifying the copolymn. compsn., melt index, and density of an ethylene- propylene-butene-1 random copolymer. CONSTITUTION:The title terpolymer comprises a random copolymer of ethylene, propylene, and butene-1, contains 90-99.5mol% ethylene units and 0.5-10mol% the sum of propylene units and butene-1 units, the molar ratio of the butene-1 unit to the propylene unit being 0.01-2, and has a melt index of 0.01-200g/10min and a density of 0.900-0.945g/cm<3>.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ethylene terpolymer and a method for producing the same. More specifically, the present invention provides ethylene,
Contains propylene and butene-1 in a specific proportion range,
The present invention relates to an ethylene-based terpolymer having a melt index and density within a specific range, and a method for producing the same. The copolymer of the present invention has tearability and cuttability (
It has an excellent balance of cuttability.

In recent years, linear low-medium density polyethylene obtained using a catalyst that combines transition metal compound components and organometallic compound components has been used in various molding fields such as film molding, extrusion molding, and injection molding. This means that linear low-medium density polyethylene has better tensile strength, tear strength, environmental stress cracking resistance (ESCR), and heat resistance than branched low-density polyethylene produced by conventional high-pressure radical polymerization. This is due to its excellent hot tank properties, surface gloss, etc.

However, among these excellent properties, the excellent properties of tensile strength and tear strength are important, for example, in cutting the film when making bags from the original film or cutting the cylindrical extrusion molded product when forming tubes. , parison cant properties during blow molding, or injection molded cans, knobs, inner stoppers, or sealing lids for containers that have a pull-off or pilfer-proof design, and if a part of them is torn off when they are used. Conversely, this is a problem when tearing or cutting properties are required for items that are to be cut or cut.

Therefore, linear low-medium density polyethylene is resistant to environmental stress cracking (
Although it has other excellent properties such as ESCR) and heat resistance, it cannot be used for applications that require easy cutting or tearing, or branched low-density polyethylene has other excellent properties. There are restrictions such as having to blend to the extent that it causes a decrease in

Linear low-medium density polyethylene, for which these drawbacks are generally pointed out, is when α-olefins containing 4 or more carbon atoms are used, especially hexene-1,4-methyl-pentene-1, octene-1, etc. This becomes noticeable when the number of carbon atoms is 5 or more. In addition, when propylene having 3 carbon atoms is used as the α-olefin, although the above-mentioned improvement in ease of cutting is certainly achieved, at the same time, the various physical properties inherent to linear low-medium density polyethylene are significantly impaired, and Even in a blend with linear low-medium density polyethylene using an α-olefin having 4 or more carbon atoms, it is difficult to strike a good balance between improving the deterioration of various physical properties and improving cantability and tearability.

On the other hand, there are also reports on various production methods and compositions for terpolymers in which propylene and α-olefin having 4 or more carbon atoms are simultaneously copolymerized (e.g., JP-A-5787405, JP-B No. 60-1882, No. 60-42805, No. 60-
No. 11925, JP-A-63-8443, JP-A No. 63-84
No. 45 and No. 63-6006 (Responses), but there is no one that aims to improve the above-mentioned easy canting properties and easy tearing properties, but rather the tensile strength inherent to linear low-medium density polyethylene, The purpose is to improve various physical properties such as tear resistance and impact resistance, and to improve transparency.
- The aim was to obtain the advantage of economical efficiency or improved productivity, which eliminates the need to use large amounts of olefins. Therefore, at present, no linear low-medium density polyethylene material has been found that solves this problem.

In view of the current situation, the present inventors have determined the tensile strength of polymers,
The present invention was completed after conducting studies with the aim of providing a polymer with an excellent balance of ease of cutting and tearing without compromising physical properties such as tear strength, ESCR1 heat resistance, hot tack properties, and surface gloss. This is what I did.

That is, the present invention first provides a random copolymer of ethylene, propylene, and butene-1, the ethylene unit being 90
~99.5 mol%, the total of each unit of propylene and butene-1 is 0.5 to 10 mol%, and the molar specific strength of butene-1 unit/propylene unit is in the range of 0.01 to 2, Meltondenox 0.01-200g/10 minutes,
The present invention provides an ethylene-based terpolymer having a density of 0.900 to 0.945 g/cffl, and secondly provides a catalyst comprising a combination of a transition metal compound component and an organometallic compound component. ethylene, propylene, and butene-1 are randomly copolymerized in the presence of
0 to 99.5 mol%, the total of each unit of propylene and butene-1 is 0.5 to 10 mol%, butene-1
The molar ratio of unit/propylene unit is in the range of 0.01 to 2, and the melt index is 0. O1~200g/10
The present invention provides a method for producing an ethylene-based terpolymer having a density of 0.900 to 0.945 g/cd.

The ethylene-based terpolymer of the present invention has the environmental stress cracking resistance (ESCR), tensile strength, tear strength, impact strength, heat resistance, hot tack property, and
It has excellent properties such as surface gloss, and is suitable for cutting, for example, cutting of film when making bags from original film, cutting of cylindrical extrusion products when forming tubes, or parison during blow molding. Cantability, injection-molded caps, inner stoppers, and sealing lids for containers have a pull-tomp or pilfer-proof design, and tearability and cutability in products that are partially torn off or cut during use. Since these problems are solved, the linear low-hollowness polyethylene is suitable for various uses that require cutability or tearability.

The ethylene-based terpolymer of the present invention is a random copolymer of ethylene, propylene, and butene-1, and contains 90 to 99.5 mol% of ethylene units, and contains propylene and butene-1. The total of each unit is 0.5 to 10 mol%, and the molar ratio of butene-1 unit/propylene unit is 0.01
~2, preferably in the range of 0.1 to 1, with a melt index of 0.01 to 200 g/10 min, and a density of 0.9
It is in the range of 00 to 0.945 g/d.

If the ethylene unit exceeds the above range, the contribution of copolymerization to strength and strength properties will be weakened, and physical rigidity will also increase, making it impossible to obtain sufficient improvement effects of the present invention. On the other hand, if it is lower than the above range, it becomes too soft and the effects of the present invention cannot be obtained.

Furthermore, if the molar ratio of butene-1 unit/propylene unit is smaller than the above range, the strength and properties of the copolymer may be good, but the tensile strength, tear strength, etc. will be at an insufficient level; conversely, if it is larger than this range, Cutting performance deteriorates.

The ethylene-based terpolymer of the present invention can be produced by random copolymerization of ethylene, propylene, and butene-1 in the presence of a catalyst containing a combination of a transition metal component and an organic metal component.

There are no particular restrictions on the catalyst or polymerization method that can be used in the present invention, and known catalysts can be used.

Examples of catalysts include Ziegler type M catalysts using compounds such as titanium and vanadium as transition metal components, Feil-impus type catalysts using compounds such as chromium, and Kaminsky type catalysts using compounds such as zirconium and hacnium. system can be used. In particular, it is preferable to use a catalyst system consisting of a transition metal catalyst component, which is a combination of a magnesium compound and a compound such as titanium or vanadium, and an organoaluminium compound.

Specifically, Special Publication No. 60-1882, No. 61-268
No. 05, No. 61-50964, No. 61-49321, No. 60-50367, JP-A-55-120.608
No. 57-180612, No. 5g-5309, No. 58-5310, No. 5B-5311, No. 5B-12
No. 7706, No. 60-258209, No. 61-236
No. 03, No. 61-285203, No. 61-28520
No. 4, No. 61-285205, No. 63-142008
A catalyst that is a combination of a magnesium-, titanium-, and halogen-containing transition metal catalyst component and an organoaluminum component, as described in the report and the like, is preferably used.

Specific examples of the transition metal catalyst component include inorganic solid carriers such as magnesium metal, magnesium hydroxide, magnesium carbonate, magnesium oxide, and magnesium chloride, and metals selected from magnesium, silicon, aluminum, and calcium containing magnesium atoms. Inorganic materials such as double salts, double oxides, carbonates, chlorides, hydroxides, etc., and those obtained by treating or reacting these inorganic solid carriers with oxygen-containing compounds, sulfur-containing compounds, hydrocarbons, and halogen-containing substances. Titanium or nonadium halide, alkoxy halogen (11, oxide,
Halogenated oxides, such as titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, monoethoxytrichlorotitanium, jetoxydichlorotitanium, triethoxymonochlorotitanium, tetraethoxytitanium, monoisoproboxy, citrichlorotitanium, diisopropoxy Tetravalent titanium compounds such as dichlorotitanium, tetraisopropoxytitanium, tetra/
Various titanium trihalides are obtained by reducing titanium halides with hydrogen, aluminum, titanium, or organometallic compounds, and titanium trihalides are obtained by reducing various titanium tetravalent halides with organometallic compounds. trivalent titanium compounds, such as compounds supported by known methods;
One or more electron-donating compounds selected from imide, phosphite, phosph, in, phosphate, etc. may be included as necessary.

Known organoaluminum compounds can be used in combination with the transition metal catalyst component, and specific examples include triethylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, diethylaluminium chloride, and ethylaluminum sesquis. Examples include chloride and mixtures thereof.

The polymerization method is not particularly limited; for example, a polymerization method in which the polyolefin particles are polymerized in the presence of the above-mentioned catalyst while maintaining them in a suspended state in a solvent, and a gas phase polymerization method in which the polymerization proceeds in a substantially solvent-free state. Polymerization method, solution method in which polymerization proceeds with the polymer dissolved in a solvent, or 200kg/c
A high temperature/high pressure bulk polymerization method in which polymerization proceeds at a pressure of i or higher, a high temperature/pressure of 150° C. or higher, etc. can be used.

The ethylene-based terpolymer of the present invention is a random copolymerization of ethylene, propylene, and butene-1, and contains 90 to 99.5 mol% of ethylene units, the total of each unit of propylene and butene-1. The amount is 0.5 to 10 mol%, and the molar ratio of butene-1 unit/propylene unit is 0.01
2, preferably 0.1 to 1, and is produced so that the melt index is 0.01 to 200 g/l 0 min and the density is 0.900 to 0.945 g/d. If the content of each unit of ethylene, propylene and butene-1 is out of the above range, a linear low-medium density polyethylene copolymer having excellent cantability or tearability cannot be obtained.

The ethylene terpolymer of the present invention includes antioxidants, ultraviolet absorbers, stabilizers such as thermal processing stabilizers, colorants, lubricants, antistatic agents, etc. that are usually added to linear low-medium density polyethylene. Additives such as titanium oxide, zeolite, talc, calcium carbonate, etc. can be added. Furthermore, branched low-density polyethylene or the like may be added without departing from the spirit of the present invention.

1 Bean ■ Hereinafter, the present invention will be specifically explained using Examples and Comparative Examples. In addition, the following method was used to measure the physical property values in the experimental examples.

(1) Melt index (Ml): JIS K
6760 (2) Density: JIS K6760 (density gradient tube method) (3) Comonomer content: "C-NMR/Gated decanobling method Measurement of comonomer content (mof%) of each terpolymer in the following examples Using a 90° pulse, the pulse interval was 15 seconds using the gated decoupling method, and the sample was an approximately 40% solution of orthodichlorohenzene, and a small amount of deuterated hanzene was added at 130°C. Comonomer Calculation of content is based on TMS (tetramethylsilane): 37
．． The integrated signal intensity of the methylene carbon in the main chain at the α position from the methyl branch near 6 ppm is 1+, and the integrated signal intensity of the methylene carbon in the main chain at the α position from the ethyl branch near 34.199 m is 12.30 Pl) near TI. The integrated intensity of the signal of the methylene carbon in the main chain that is one or more positions away from all branches was set to 13, and the calculation was performed using the following formula.

Example 1, Comparative Examples 1 to 3 A gas phase fluidized bed reactor similar to that used in Examples 1 to 9 of JP-A-55-120608 was used.
The catalyst component (A) synthesized in the same manner as in Example 1 of Publication No. 142008 was mixed with triethylaluminum (TEA).
It was used together with a promoter in the same manner as in Example 1 of JP-A-63-142008. The polymerization conditions were as shown in Table 1. As a result, an ethylene/propylene/butene terpolymer as shown in Table 1 was obtained.

The obtained copolymer was made into pellets using a uniaxial granulator, and
A film having a thickness of 30 μm was formed using a mmφ inflation film forming machine at a die temperature of 200°C. This film and a polyester biaxially stretched film with a thickness of 0.1 mm are layered on the bottom as a support sheet, and this is used as an unused office punch (manufactured by LION Office Machine, hole diameter: 6 mm).
Place the hole on the hole of the hole (φ, drilling capacity: 3 m), fix it on the Instron autograph, and press the spring-type pushing part from above at a constant speed of 500 mm/min to make the hole. The condition was observed and the cuttability was evaluated as follows.

Judgment Criteria: O: There are no whiskers or deformations in the hole, and the hole is well drilled.

△D Apparently there is a hole, but there are no holes left. Beards and deformities can be seen.

X: Many whiskers and deformities are seen in the drilling trace, and the drilling is incomplete and dirty.

At the same time, these films were tested for Elmendorf tear strength (according to JIS Z1702) and tensile strength test (JIS Z1702).
Z1702) and dirt drop impact strength tests (ASTM D1709) were conducted. These results are shown in Table 1 together with comparative examples.

As shown in Table 1, it can be seen that the strength and torsional properties of Example 1 were improved over the corresponding Comparative Examples 1 to 3 without significantly impairing the various physical properties.

Examples 2 to 3, Comparative Examples 4 to 6 Using the same catalyst and polymerization method as in Example 1 (see Table 2 for polymerization conditions), ethylene/propylene/butene terpolymers as shown in Table 2 were obtained. Ta.

The obtained copolymer was made into pellets using an axle granulator, and further, using an injection molding machine (L590B manufactured by Toshiba Machine ■, complete set of 40 mm diameter in-line screw), the injection pressure was 500 k.
g/ciG, molding temperature 200°C1 mold cooling water temperature 40
A stopper with a ring pull top having a diameter of 20 mφ was injection molded under conditions of °C. The pull top of the resulting stopper with a ring pull top was torn off, the cut state of the score portion was observed, and the ease of tearing was evaluated as follows.

Judgment Criteria: ○: There are no whiskers in the tear marks, and the torn pieces are cleanly torn off.

Δ: It has been torn off, but it has been torn off. The appearance of whiskers can be seen on the scratch marks.

X: There are many whiskers on the tear marks. And dirty.

Further, this stopper was fixed as shown in FIG. 1, and the pull-top portion was pulled upward at a constant speed of 500 mm/min using an autograph manufactured by Instron, and the maximum tensile strength at that time was measured.

In addition, these pellets were compression molded at 160°C to obtain a sheet with a thickness of 2IIIn, which was subjected to a tensile strength and elongation test (JASK
6760), tensile impact strength test (ASTM 018
22 compliant, 23°C), and ESCR test (ASTM
D1693 compliant) was implemented. Comparative Example 4
-6 are shown in Table 2.

From Table 2, it can be seen that Examples 2 to 3 have improved tearability compared to the corresponding comparative examples without impairing physical properties such as ESCR and impact strength.

No. table

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a test device for tearing off a stopper with a pull top. 1... Fixed stand, 2... Stopper with pull top, 3
···hook

Claims (2)

[Claims] (1) A random copolymer of ethylene, propylene, and butene-1, in which the ethylene unit is 90 to 99.5 mol%, and the total of each unit of propylene and butene-1 is 0.5
~10 mol%, and the molar ratio of butene-1 unit/propylene unit is in the range of 0.01 to 2, the melt index is 0.01 to 200 g/10 min, and the density is 0.9
00 to 0.945 g/cm^3. (2) In the presence of a catalyst that combines a transition metal compound component and an organometallic compound component, ethylene, propylene and butene
1 is randomly copolymerized, and the ethylene units are 90 to 99.
．． 5 mol%, the total of each unit of propylene and butene-1 is 0.5 to 10 mol%, and the molar ratio of butene-1 unit/propylene unit is in the range of 0.01 to 2, and the melt index is A method for producing an ethylene terpolymer having a density of 0.01 to 200 g/10 minutes and a density of 0.900 to 0.945 g/cm^3.